Dirac spinors and tachyon quantization

Dirac spinors for spin-1/2 free tachyons are derived from the Dirac and Kle in-Gordon equations in terms of the standard helicity representation of the Poincare group and superluminal transformations (SLTs). It is shown that t he proposed theory of second quantization is Lorentz invariant without inve rting the spin-statistics relationship and without introducing indefinite p seudotachyonic states. Second quantized theory of spin-1/2 tachyons in the time-energy representation shows that tachyons are localized in time and th at the most natural space for the description of tachyons is T-4-space. It has been emphasized that on passing from R-4-space (bradyons) to T-4-space (tachyons) via either, i.e., complex or real SLTs, tachyons behave in T-4-s pace exactly as bradyons do in R-4-space. T-4-space can be visualized as an internal space for a subluminal observer while R-4-space appears as an int ernal space for a superluminal observer.